Lamp socket



July 4, 1933. c. E. GODLEY v 1,915'194 LAMP SOCKET Filed Sept. 17, 1930 V Jwoontoz Patented July 4, 1933 UNITED STATES PATE NT 1 OFFICE CHARLES E. GODLEY, F YPSILAN'I'I, MICHIGAN, ASSIGNOR TO GENERAL MOTORS RESEARGH CORPORATION, OF DETROIT, MICHIGAN, A CORPORATION OF DELAWARE LAMP sooner Application filed September 17, 1930. Serial No. 482,469.

and particularly with sockets for receiving them. The single filament and two filament bulbs now commonly used are provided with pins arranged diametrically opposite each other and adapted to be received in bayonet a wide use many service possible for the car slots formed in the socket. Since the single filament bulbs are provided with a single central contact, and the two filament bulbs are provided with a pair of diametrically spaced contacts, and with filaments of identical construction, and the filaments are symmetrically arranged in the bulb, it is immaterial which way the bulbs are mounted in the socket. However in case filaments of unequal candle power are used, or more than two filaments are provided, it is desirable that the bulbs be inserted in the socket right side up, and that the construction be such that the bulbs cannot be put in the socket in any other way. It is likewise desirable that the design of socket be such that it will receive the present single filament and two filament bulbs, for until other types of bulbs go into stations will carry none but the older types of bulbs and it should be owner to use one of the old bulbs for replacement in case the others are not available.

My invention consists in a novel construction of socket adapted to receive either new or old style bulbs, and in' case of the new style bulbs, to so cooperate with the bulb as to make it impossible to insert the bulb with the wrong side up.

' While the old type of bulb may as usual be inserted with either side up,

the new type of bulb with the ofi center pin may be inserted only in one position for the enlargement of the slot extends on but one side of a diameter passing through one edge of the throats of the slots.

Figure 1 is a section through a reflector equipped with a socket in which my improved bulb is mounted.

Figure 2 is a section on line 22 ofcFigure 1.

Figure 3 is a section corresponding to Figure 2 but showing a conventional bulb in the socket.

Figure 4 is a perspective view proved socket.

In Figure 1 I have shown a portion of an automobile headlamp reflector 10, in which is secured my improved socket 12. The socket is secured in the reflector by any suitable of my imsocket, and wedges against lugs 18 formed on the socket, urging it rearwardly, and bears against lugs 20 formed on plate 22 carrying contacts 24, urging the contacts forwardly into contact with the cooperating contacts 26 formed on the bulb base 28. I have illustrateda bulb of the three filament type, provided with three contacts. The shell 30 is connected to the filaments to serve as a common ground for the filaments.

Referring now to Figure 2 it will be noted that the base 28 is provided with pins one of which, marked 32, is angularly offset with respect to line 34 drawn through the other pin 36 and the axis of the bulb. It will also be noted by reference to Figure 4 that the socket 12 is provided with bayonet slots 38 and 40. Bayonet slot 38 is of conventional size but bayonet slot 40 extends circumferentially a greater distance than slot 38 and is provided with a widened throat 42. Specifically the slot 40 is of the same angular extent as the slot. 38 plus the amount the pin 32 is angularly offset with respect to the line 34. The throat 42 is widened a like amount.

In Figure 2 I have shown my improved bulb mounted in the socket. It will be noted that the pin 36 occupies the usual position in the depression provided at 39 in one end of the slot 38. It will be noted that pin 32 occupies a position at the far end of the enlarged slot 40. It will be noted that the arrangement of pins and slots makes it impossible to insert the bulb in the socket with the other side up.

In Figure 3 I have shown a conventional bulb mounted in the socket. It will be noted that the pin, numbered 44, occupies the same position in slot 38 as pin 36 on my improved socket, but pin 46 rests on its seat immediately adjacent the throat 42. Obviously, the bulb may be inserted in the socket with either side up. In this figure I have indicated contacts 24 in dotted lines. It will be noted that two of these make satisfactory contact with the contacts on the lamp base. The

' third contact 26 will not be used.

I wish to call attention to the fact that in Figure 1 I have, for the purpose of illustration, shown the filaments 50, 52 and 54in an incorrect position. Actually the filaments should be rotated 90 about the bulb axis so as to bring the inclined filament 54: to the front. This brings the apices of the V-shaped filaments 50 and 52 in the same plane as the pin 36. The arrangement is convenient in locating the parts during manufacture of the bulb.

I have shown the bayonet slot 40 provided with two seats, one for the pin of the three filament bulb, and the other for the pin oi the two filament bulb. Obviously, the two seats may be combined, eliminating. the ridge 56 between them. If desired, the outer ridge 58 may be omitted, the opposite slot then being relied upon to pregent radial displacement of the bulb.

I claim:

A lamp socket for use either with bulbs having locating pins at the ends of a diameter through the base or with bulbs having one of the pins slightly offset angularly with respect to a line passing through the center of the base and the other pin, said socket being provided with bayonet slots having entrance throats and pin seats, the entrance throats lying at the opposite ends of a diameter drawn through the socket, said slots extending angularly away from said diameter'in the same direction, one of said slots being of greater angular extent than the other and having a throat and pin seat of greater angular extent than the other by an amount equal to or greater than theamount of angular offset of oneof said pins to permit the slot to receive and hold bulbs having either arrangement of locating pins.

In testimony whereof I aflix my signature.

CHARLES E. GODLEY. 

